Removing incrustation formed on metallic surfaces



Patented May 20, 1930 UNITED STATES PATENT OFFICE...

RICHARD SELIGMAN, OF WANDSWORTH, LONDON, ENGLAND REMOVING INCRUSTATION FORMED 0N METALLIC SURFACES No Drawing. Application filed August 1, 1927, Serial No. 210,017, and in Great Britain November 4, 1926.

The present invention aims to facilitate the removalof the incrustations which form on metallicsurfaces which are in contact with hot milk.

It has been found that the incrustation or surface coating which forms on metal surfaces used for heating milk and is regarded or known as calcium caseinogenate is readily disintegrated by subjecting it to a solution of an acid, but some provision must be made to prevent the acids attacking the metal surface actively.

According to the present invention the incrustation is removed by treating the surfaces with an acid which also contains casein or gelatine as a protective-agent to prevent or lessen the action of the acid on the metallic surfaces or objects.

By way of example only, good results have been obtained by the use of a weak solution of medicinal (British Pharmacopoeia) orthophosphoric acid, the strength of the solution being 2%, the temperature of the solution being between 85 to 100 the treatment being about 30 minutes.

Where such metallic surfaces are coated with casein, the previous addition of protective material is not howeverfonnd essential when dealing with milk incrustations as the solution may be circulated rapidly over the metal surfaces by means of a pump the temperature being maintained by steam or some similar device. Alternatively the articles to be freed from scale may be immersed in abath of the solution which is preferably kept in activecirculation and appropriately maintained at the desired temperature.

The following is an example of the proportions of the materials used in forming a bath:

97 parts by weight of water.

2 parts by weight of ()l't-l10-Pl108pl101l0 acid.

1 part by weight of casein.

What I claim is 1. The process for removing the incrustation which forms on a metallic surface in contact with hot milk which consists in treat- C., and the time of 7 ing the surface with a solution containing ortho-phosphoric acid, casein, and water.

2. The process for removing the incrustation which forms on a metallic surface in contact with hot milk which consists in treating the surface with a solution of ortho-phosphoric acid-solution in the presence of casein derived from the incrustation itself, said casein being a protective agent which prevents or minimizes .the action of the acid upon the metallic surface.

3. The process for removing the incrustation which forms on a metallic surface in contact with hot milk .which consists in treating the surface with pure ortho-phosphoric acid said pure ortho-phosphoric acid containing a colloid soluble in said acid to prevent or minimize the action of the pure ortho-phosphoric acid upon the metallic surface itself.

4. The process for removing the incrust-ation which forms on a metallic surface in contact with hot milk which consists in treating the surface with a solution of pure orthophosphoric acid in the presence of a. colloidsoluble in said acid to prevent. or. minimize the actioniof the acid upon the metallic surface itself.

5. The process for removing the incruetation which forms on a metallic surface in contact with hot milk which consists in treating the surface with pure ortho-phosphoric in the presence of casein derived from the incrustation itself, said casein being a protective agent which prevents or minimizes the action of the pure ortho-phosphoric acid upon the metallic surface.

In testimony whereof, I aflix my signature.

, RICHARD SELIGMAN. 

